Banff by Night


Milky Way Reflections at Bow Lake

Three perfect nights in July provided opportunities to capture the night sky at popular sites in Banff National Park.

When the weather forecast in mid-July looked so promising I made an impromptu trip to Banff to shoot nightscapes and time-lapses under unusually clear skies. Clouds are often the norm in the mountains or, increasingly these days, forest fire smoke in late summer.

But from July 15 to 17 the skies could not have been clearer, except for the clouds that rolled in late on my last night, when I was happy to pack up and get some sleep.

Conjunction over the Continental Divide with Train

My first priority was to shoot the marvellous close conjunction of the Moon and Venus on July 15. I did so from the Storm Mountain viewpoint on the Bow Valley Parkway, with a cooperative train also coming through the scene at the right time.

The Milky Way and Mars over Storm Mountain

This was the view later with the Milky Way and Mars over Bow Valley and Storm Mountain.

Bow Lake by Night Panorama

The next night, July 16, was one of the most perfect I had ever seen in the Rockies. Crystal clear skies, calm winds, and great lake reflections made for a picture-perfect night at Bow Lake on the Icefields Parkway. Above is a 360° panorama shot toward the end of the night when the galactic centre of the Milky Way was over Bow Glacier.

Streaks of green airglow arc across the south, while to the north the sky is purple from a faint display of aurora.

Earlier that night the usual auroral arc known as Steve put in an unexpected appearance. It was just a grey band to the eye, but the camera picked up Steve’s usual pink colours. Another photographer from the U.S. who showed up had no idea there was an aurora happening until I pointed it out.

Mars and the Milky Way at Herbert Lake

My last night was at Herbert Lake, a small pond great for capturing reflections of the mountains around Lake Louise, and the Milky Way. Here, brilliant Mars, so photogenic this summer, also reflects in the still waters.

At each site I shot time-lapses, and used those frames to have some fun with star trail stacking, showing the stars turning from east to west and reflected in the lake waters, and with a single still image taken at the end of the sequence layered in to show the untrailed sky and Milky Way.

But I also turned those frames into time-lapse movies, and incorporated them into a new music video, along with some favourite older clips reprocessed for this new video.

Banff by Night (4K) from Alan Dyer on Vimeo.

Enjoy! And do enlarge to full screen. The video is also in 4K resolution.

Clear skies!

— Alan, August 2, 2018 / © 2018 Alan Dyer / AmazingSky.com

 

Mars and Jupiter in the Morning


Jupiter and Mars at Dawn

Mars and Jupiter are meeting up in the morning sky. Soon they’ll be joined by the Moon.

Here’s a heads up for one of the best planet conjunctions of the year. Mars and Jupiter are now close together in the dawn sky to the south, and getting closer!

Above is the actual view on the morning of January 4, with Jupiter the brightest of a trio of objects. Mars is reddish and in the middle. The object at right is the star Alpha Librae, also known as Zubenelgenubi in Libra.

Jan 6 Morning Sky
Looking south-southeast on January 6

As shown in the simulation above, on the morning of January 6 Mars and Jupiter will be only 1/3rd of a degree apart (20 arc minutes), so close that dimmer Mars might not be obvious to the naked eye next to bright Jupiter. But use binoculars to show the planet pair.

The next morning, on January 7, they will appear almost as close, as Jupiter climbs higher past Mars.

Jan 11 Morning Sky
Looking south-southeast on January 11

As shown here, on the morning of January 11 the waning crescent Moon will sit only 4 degrees from the planet pair, with all three worlds gathered close enough for binoculars to frame the scene.

With sunrise coming late on winter mornings, it doesn’t take an early rise to take in the dawn scene. Make a note to take a look about 6:30 to 7:00 a.m. over the next week.


POSTSCRIPT added January 6:

Here’s the real scene from the morning of January 6, with Mars and Jupiter just 16 arc minutes apart, very close but still easy to distinguish  with the naked eye. Jupiter did not overwhelm Mars.

Jupiter and Mars in Conjunction at Dawn

Thanks and Clear skies!

— Alan, January 4, 2018 / © 2018 Alan Dyer / amazingsky.com

Conjunctions, Satellites & Auroras, Oh My!


Friday the 13th Aurora Title

October has brought clear skies and some fine celestial sights. Here’s a potpourri of what was up from home. 

We’ve enjoyed some lovely early autumn weather here in southern Alberta, providing great opportunities to see and shoot a series of astronomical events.


Conjunctions

Venus & Mars in Close Conjunction #2 (Oct 5, 2017)
Venus and Mars in close conjunction in the dawn sky on October 5, 2017. Venus is the brightest object; Mars is below it; while the star above Venus is 4th magnitude Sigma Leonis. The foreground is illuminated by light from the setting Full Moon in the west. This is a single 1-second exposure with the 135mm lens at f/2 and Canon 60Da at ISO 800. 

On October 5, Venus and Mars appeared a fraction of a degree apart in the dawn twilight. Venus is the brightest object, just above dimmer but red Mars. This was one of the closest planet conjunctions of 2017. Mars will appear much brighter in July and August 2018 when it makes its closest approach to Earth since 2003.


Satellites: The Space Station

Overhead Pass of the Space Station in Moonlight
An overhead pass of the ISS on October 5, 2017, with the Full Moon rising in the east at left. The ISS is moving from west (at right) to east (at left), passing nearly overhead at the zenith at centre. North is at the top, south at bottom in this fish-eye lens image with an 8mm Sigma fish-eye lens on the Canon 6D MkII camera. This is a stack of 56 exposures, each 4 seconds long at an interval of 1 second. 

The Space Station made a series of ideal evening passes in early October, flying right overhead from my site at latitude 51° N. I captured it in a series of stacked still images, so it appears as a dashed line across the sky. In reality it looks like a very bright star, outshining any other natural star. Here, it appears to fly toward the rising Moon.


Satellites: Iridiums

Twin Iridium Satellite Flares (October 9, 2017)
A pair of nearly simultaneous and parallel Iridium satellite flares, on October 9, 2017, as they descended into the north. The left or westerly flare was much brighter and with a sharp rise and fall in brightness. While it was predicted to be mag. -4.4 I think it got much brighter, perhaps mag -7, but very briefly. These are Iridium 90 (left) and Iridium 50 (right). This is a stack of 40+ exposures each, 2 seconds at 1-second intervals, with the Sigma 24mm lens at f/1.4 and Nikon D750 at ISO 6400.

Often appearing brighter than even the ISS, Iridium satellite flares can blaze brighter than even Venus at its best. One did so here, above, in another time-lapse of a pair of Iridium satellites that traveled in parallel and flared at almost the same time. But the orientation of the reflective antennas that create these flares must have been better on the left Iridium as it really shot up in brilliance for a few seconds.


Auroras

Aurora and Circumpolar Star Trails (Oct, 13, 2017)
A circumpolar star trail composite with Northern Lights, on October 13, 2017, shot from home in southern Alberta. The Big Dipper is at bottom centre; Polaris is at top centre at the axis of the rotation. The bottom edge of the curtains are rimmed with a pink fringe from nitrogen. This is a stack of 200 frames taken mostly when the aurora was a quiescent arc across the north before the substorm hit. An additional single exposure is layered in taken about 1 minute after the main star trail set to add the final end point stars after a gap in the trails. Stacking was with the Advanced Stacker Plus actions using the Ultrastreaks mode to add the direction of motion from the tapering trails. Each frame is 3 seconds at f/2 and ISO 6400 wth the Sigma 14mm lens and Nikon D750.

Little in the sky beats a fine aurora display and we’ve had several of late, despite the Sun being spotless and nearing a low ebb in its activity. The above shot is a composite stack of 200 images, showing the stars circling the celestial pole above the main auroral arc, and taken on Friday the 13th.

Aurora from October 13, 2013
A decent aurora across the north from home in southern Alberta, on Friday the 13th, October, 2017, though these frames were taken after midnight MDT. 3 seconds at f/2 and ISO 6400 wth the Sigma 14mm lens and Nikon D750.

This frame, from some 1300 I shot this night, October 13, captures the main auroral arc and a diffuse patch of green above that pulsed on and off.

You can see the time-lapse here in my short music video on Vimeo.

Friday the 13th Aurora from Alan Dyer on Vimeo.

It’s in 4K if your monitor and computer are capable. It nicely shows the development of the aurora this night, from a quiescent arc, through a brief sub-storm outburst, then into pulsing and flickering patches. Enjoy!


What all these scenes have in common is that they were all shot from home, in my backyard. It is wonderful to live in a rural area and to be able to step outside and see these sites easily by just looking up!

— Alan, October 16, 2017 / © 2017 Alan Dyer / AmazingSky.com 

 

The Cadence of the Moving Sky


Saturn, Mars and the Milky Way over the Bow River

Saturn, Mars and the Milky Way appeared in the twilight over the Bow River.

I shot this scene on August 24 from the viewpoint at Blackfoot Crossing Historical Park, overlooking the Bow River. Mars appears between Saturn above and Antares below, in a line of objects west of the Milky Way.

The valley below is the traditional meeting place of the Blackfoot Nation, and the site of the signing of Treaty Seven between Chief Crowfoot and Colonel MacLeod of the North West Mounted Police in 1877.

The image is a panorama of two images, each 20-second exposures at f/2 and ISO 1600 with the 24mm lens. I shot them just prior to shooting time-lapses of the moving sky, using two cameras to create a comparison pair of videos, to illustrate the choices in setting the cadence when shooting time-lapses.

The movies, embedded here, will be in the next edition of my Nightscapes and Time-Lapse ebook, with the current version linked to below. The text explains what the videos are showing.

 

Choose Your Style

When shooting frames destined for a time-lapse movie we have a choice:

  • Shoot fewer but longer exposures at slower ISOs and/or smaller apertures.

OR …

  • Shoot lots of short exposures at high ISOs and/or wide apertures.

 

The former yields greater depth of field; the latter produces more noise. But with time-lapses, the variations also affect the mood of a movie in playback.

This comparison shows a pair of movies, both rendered at 30 frames per second:

Clip #1 was taken over 2 hours using 20-second exposures, all at ISO 2000 and f/2 with 1-second intervals. The result was 300 frames.

Clip #2 was taken over 1 hour using 5-second exposures also at f/2 and 1-second intervals, but at ISO 8000. The result was 600 frames: twice as many frames in half the time.

Clip #1 shows fast sky motion. Clip #2 shows slow motion.

Clip #2 exhibits enough noise that I couldn’t bring out the dark foreground as well as in Clip #1. Clip 2 exhibits a slower, more graceful motion. And it better “time-resolves” fast-moving content such as cars and aircraft.

Which is better? It depends …

Long = Fast

The movie taken at a longer, slower cadence (using longer exposures) and requiring 2 hours to capture 300 frames resulted in fast, dramatic sky motion when played back. Two hours of sky motion are being compressed into 10 seconds of playback at 30 frames per second. You might like that if you want a dramatic, high-energy feel.

Short = Slow

By comparison, the movie that packed 600 frames into just an hour of shooting (by using short exposures taken at fast apertures or fast ISOs) produced a movie where the sky moves very slowly during its 10 seconds of playback, also at 30 frames per second. You might like that if you want a slow, peaceful mood to your movies.

So, if you want your movie to have a slow, quiet feel, shoot lots of short exposures. But, if you want your movie to have a fast, high-energy feel, shoot long exposures.

As an aside – all purchasers of the current edition of my ebook will get the updated version free of charge via the iBooks Store once it is published later this year. 

— Alan, August 26, 2016 / © 2016 Alan Dyer / AmazingSky.com

 

Moon and Star Conjunction


Moon and Aldebaran (July 29, 2016)

The waning Moon shone near the bright star Aldebaran in the dawn sky.

This was a beautiful sight this morning, before dawn on July 29. The crescent Moon, its night side illuminated by Earthshine, shone just below the brightest star in Taurus.

We are currently in 3-year period when the Moon’s path is taking it near or in front of Aldebaran every month. However, most of these occultations or conjunctions are not well-timed for any particular location. And many involve the too-brilliant gibbous or full Moon.

But this morning the timing and Moon phase were perfect. From my longitude on Earth in Alberta, the Moon passed closest to the star just before the sky was getting too bright with dawn. Having them set against the deep blue twilight was perfect.

From farther east the Moon would not have appeared as close to Aldebaran as this before sunrise. From farther west the Moon and star would have appeared much lower in the sky at closest approach.

Moon & Aldebaran Screen

TECHNICAL:

For this image I shot 6 exposures, from 2 seconds for the Earthshine, twilight sky colour and stars, to 1/125th second for the bright crescent. I then stacked, aligned, and blended them together using luminosity masks – masks that hide or reveal parts of the image based on the brightness of the scene. You can see them in the Photoshop screen shot – Click on the image to enlarge it.

How do you create these masks?

• Turn off all the layers except the one you want to create a mask for.

• Go to Channels and Command/Control Click on the RGB Channel.

• That automatically selects all the highlights.

• Go back to the image layer and then hit the Add Mask button down at the bottom of the Layers panel (the rectangle with the black dot in it).

• Done. Repeat that for each image layer.

More traditional high dynamic range or “HDR” stacking left odd colour fringing artifacts and double images on the slowly moving Moon, despite applying what is called “de-ghosting” and despite using a mount tracking at the lunar rate. I tried merging the images with HDR, but it didn’t work.

A nifty Photoshop action from the Astronomy Tools set by Noel Carboni added the diffraction spikes.

I shot all images with the 130mm Astro-Physics refractor at f/6 and the Canon 60Da camera at ISO 400.

— Alan, July 29, 2016 / © 2016 Alan Dyer / www.amazingsky.com

Planets in the January Dawn


Waning Moon with Venus & Saturn in Twilight (Jan 6, 2016)

The waning Moon joined Venus and Saturn on a cold winter dawn.

This was the scene this morning, January 6, as the waning crescent Moon met with Venus (bright, at centre) and Saturn (below and left of Venus) in the cold morning twilight.

The grouping appeared above the stars of Scorpius. Antares is just above the treetops.

The top image is with the Canon 60Da and 50mm lens.

The view below, with the 135mm telephoto and Canon 6D camera, is from a half hour earlier before the sky began to brighten with morning twilight.

Waning Moon with Venus & Saturn (Jan 6, 2016)
The waning crescent Moon above Venus and Saturn (dimmer and below Venus) in the pre-dawn sky on January 6, 2016, taken from home on a cold winter morning at -20° C. This is a composite of a long exposure (8s) for the ground, a slightly shorter exposure (6s) for the sky, and shorter exposures for the Moon to avoid it being totally overexposed and to preserve the Earthshine. All with the 135mm lens and Canon 6D.

Venus passes very close to Saturn this weekend, with the two worlds appearing within a telescope field on the mornings of January 8 and 9. Get up early before sunrise and look southeast. Binoculars will provide a superb view.

Venus is hard to miss, but is now dropping lower each morning and will soon be gone from view as it ends its wonderful appearance as a morning star.

— Alan, January 6, 2016 / © 2016 Alan Dyer / www.amazingsky.com

 

Venus and the Comet


Comet Catalina near Venus (Dec 9, 2015)

Comet Catalina sports two tails as it moves past Venus in the dawn sky.

This was the view this morning, December 9, from my site in Arizona, of Comet Catalina near Venus in the dawn sky. This is a telephoto lens shot that provides a view similar in size to what binoculars show.

However, the blue ion tail visible here stretching back several degrees is mostly a photographic target. Visually, just Catalina’s short, stubby dust tail at lower right is obvious.

The ion tail points away from the Sun, while the dust tail extends along the comet’s orbit, showing where the comet has been.

The view, both visually and photographically, of the comet will improve as it climbs higher into the eastern morning sky and as it moves away from the glare of Venus. The Moon is also now gone from the dawn, at least for the next couple of weeks.

The comet is dimmer than expected but should at least maintain this brightness for the next month or so.

Technical:

This is a stack of 5 x 90-second exposures, taken with the 135mm telephoto and 1.4x extender for a focal length of 190mm, at f/2.8 and with the Canon 5D MkII at ISO 1600, tracked on the iOptron Sky-Tracker. Two other exposures, of 15s and 1s, were blended in with luminosity masks to reduce the glare of Venus to a smaller size.

— Alan, December 9, 2015 / © 2015 Alan Dyer / www.amazingsky.com